The answer is D, only B is a mineral. I always look at it as mineral's atoms are usually closer together but always check your answers.
The frequency of the ultrasound is (converting in Hz)

while the speed of sound in the body is

We can calculate the wavelength of the ultrasound in the body by using the relationship betwen frequency, wavelength and speed of the wave:
Answer: 99.64 nm (≅ 100 nm)
Explanation: In order to explain this problem we have to obtain destructive inteference from two waves that reflect in the film and lens surface so both waves have a λ/2 shift then we have to get a difference path (2L) equal to an odd number of the half wavelegth.
Then we have the following expression:
L=(m+1/2)* λ/(2*n2); where n2 is the refractive index of the coating
for m=0 we have the minimum thickness for the coating
L=λ/(4*n2)=99.64 nm (≅ 100 nm)
Kinematic equations are the equations that help to describe the motion of an object in constant acceleration. There are 4 of them and they are used in problems regarding motion when the variables are presented in them.
Ex:
Use V=Vo + at if you need to find velocity, and acceleration, time, and Vo are given to you
Answer: I'm pretty sure that you just have to make sure that all of the elements have the same charge on both sides.
Explanation: Example: 2CO2+ 4CO2----- C6O10